function update(key, target, point) {
	var uri = "/update";
	var data = { key: key, statistic: target}
	var callback = function(data) {
		var value = new Number(data[target]);
		var digit = Math.pow(10, point);
		$("#" + target).html(Math.round(value * digit) / digit);
	};
	$.getJSON(uri, data, callback);
}
